The optimistic reports of numerous foreign clinicians on the use of therapeutic pneumothorax in cases of lobar pneumonia and the encouraging results obtained by us in our first experimental study on dogs1 have prompted a number of American physicians to resort to artificial pneumothorax in the treatment of lobar pneumonia. The present clinical status of this procedure has recently been presented.2 No further experimental work on animals has been published, and no studies on patients have been made in an effort to explain the modus operandi of this treatment, except those of Blake, Howard and Hull.3
These authors studied the agglutinins of the serum of twenty-two patients and found that "agglutinins apparently appear in the blood just about the same as they do in the untreated cases." This is significant, because in some of the cases clinical recovery as judged by the usual criteria occurred as early